The emotional pitch of World War I did not abate with the armistice, and rampant inflation, unemployment, massive and violent strikes, and brutal race riots in the United States contributed to a sense of fear and foreboding in 1919. A mail bomb plot, consisting of 36 explosive packages designed to go off on May Day, 1919, triggered a grave fear that a Bolshevikconspiracy sought the overthrow of the United States. On June 2, 1919, a second series of bombings took place, destroying Palmer’s home and leading to increased public pressure for action against the radical agitators.

Palmer was a latecomer to the anticommunist cause and had a history of supporting civil liberties. However, he was ambitious to obtain the Democratic nomination for the presidency in 1920 and believed that he could establish himself as the law-and-order candidate. Together with J. Edgar Hoover, Palmer created the General Intelligence Division in the Federal Bureau of Investigation and secured an increase in funds from Congress to devote to anticommunist activities by the Justice Department.

On November 7, 1919 (the second anniversary of the Bolshevik takeover of Russia), U.S. federal and local authorities raided the headquarters of the Union of Russian Workers in New York City and arrested more than 200 individuals. On November 25 a second raid on the Union of Russian Workers headquarters unveiled a false wall and a bomb factory, confirming suspicions that the union harboured revolutionary intentions. Palmer believed that the way to deal with the radicals was to deport the immigrants. On December 21, 249 radicals, including anarchist Emma Goldman, were packed aboard the USS Buford, which the press dubbed the Soviet Ark, and deported to Russia. On January 2, 1920, the most spectacular of the Palmer Raids took place, when thousands of individuals (estimates vary between 3,000 and 10,000) were arrested in more than 30 cities. The following day, federal, state, and local agents conducted further raids. In all the Palmer Raids, arrests greatly exceeded the number of warrants that had been obtained from the courts, and many of those arrested were guilty of nothing more than having a foreign accent.

Palmer declared the raids a success but announced that the work was far from done. He claimed that there were still more than 300,000 dangerous communists inside the United States. Local authorities lacked the facilities to hold the arrestees from the January raids, and Palmer sent a large number of suspected radicals to the Bureau of Immigration for deportation. Acting Secretary of Labor Louis Post, however, did not share Palmer’s fear of radical aliens and reversed more than 70 percent of the 1,600 deportation warrants.

Meantime, American public opinion shifted under Palmer’s feet. As news of the brutality of the raids became public and the constitutionality of the actions was brought into question, many, including the National Civil Liberties Bureau, publicly challenged Palmer’s actions. Palmer’s unfulfilled dire predictions of a May Day 1920 revolution destroyed his credibility with the public, diminishing the Red Scare and ending the Palmer Raids.

Palmer RaidsFront page of the Chicago Federation of Labor's newspaper, The New Majority, January 10, 1920, featuring an article that describes the Palmer Raids as terrorism.Newberry Library, Case Oversize HD6500 .N5